292 research outputs found
EFFICACY AND TOLERABILITY OF LERCANIDIPINE IN ELDERLY PATIENTS WITH MILD TO MODERATE HYPERTENSION IN A PLACEBO-CONTROLLED, DOUBLE-BLIND STUDY
Цель. Оценить эффективность лерканидипина (антагониста кальция из группы дигидропиридинов) у пожилых больных артериальной гипертонией (АГ). Материал и методы. В многоцентровое рандомизированное двойное слепое плацебо-контролируемое исследование включены 144 больных в возрасте 60-85 лет, разделенных на группы, получавших лерканидипин в дозе 10 мг или плацебо в течение 4 нед. При недостаточной антигипертензивной эффективности исходную дозу лерканидипина увеличивали (вплоть до 30 мг один раз/день в течение 12 нед). Результаты. Диастолическое артериальное давление (АД) под действием лерканидипина в дозе 10 мг снижалось в большей степени (-10,3 мм рт.ст.), чем под действием плацебо (-6,1 мм рт.ст.; p<0,05). Доля больных, положительно ответивших на прием лерканидипина, также была выше, чем при приеме плацебо (59,1% и 37,8 %, соответственно; p<0,05). При увеличении дозы препарата до 20 мг доля больных, положительно ответивших на лечение, возросла до 69,4%; увеличение дозы до 30 мг потребовалось лишь небольшому числу пациентов. Частота сердечных сокращений и лабораторные показатели на фоне лечения не менялись. Процент больных с побочными эффектами был одинаковым в обеих группах. Заключение. Прием лерканидипина один раз в день значительно снижает АД у пожилых пациентов с легкой и умеренной АГ . Эффект сохраняется в течение 24 ч и не сопровождается рефлекторной тахикардией. Препарат хорошо переносится и, учитывая его фармакологические и фармакодинамические особенности, может быть рекомендован, особенно пожилым пациентам
The artificial retina processor for track reconstruction at the LHC crossing rate
We present results of an R&D study for a specialized processor capable of
precisely reconstructing, in pixel detectors, hundreds of charged-particle
tracks from high-energy collisions at 40 MHz rate. We apply a highly parallel
pattern-recognition algorithm, inspired by studies of the processing of visual
images by the brain as it happens in nature, and describe in detail an
efficient hardware implementation in high-speed, high-bandwidth FPGA devices.
This is the first detailed demonstration of reconstruction of offline-quality
tracks at 40 MHz and makes the device suitable for processing Large Hadron
Collider events at the full crossing frequency.Comment: 4th draft of WIT proceedings modified according to JINST referee's
comments. 10 pages, 6 figures, 2 table
Observation of resonances consistent with pentaquark states in decays
Observations of exotic structures in the channel, that we refer to
as pentaquark-charmonium states, in decays are
presented. The data sample corresponds to an integrated luminosity of 3/fb
acquired with the LHCb detector from 7 and 8 TeV pp collisions. An amplitude
analysis is performed on the three-body final-state that reproduces the
two-body mass and angular distributions. To obtain a satisfactory fit of the
structures seen in the mass spectrum, it is necessary to include two
Breit-Wigner amplitudes that each describe a resonant state. The significance
of each of these resonances is more than 9 standard deviations. One has a mass
of MeV and a width of MeV, while the second
is narrower, with a mass of MeV and a width of MeV. The preferred assignments are of opposite parity, with one
state having spin 3/2 and the other 5/2.Comment: 48 pages, 18 figures including the supplementary material, v2 after
referee's comments, now 19 figure
Search for hidden-sector bosons in decays
A search is presented for hidden-sector bosons, , produced in the decay
, with and
. The search is performed using -collision data
corresponding to 3.0 fb collected with the LHCb detector. No significant
signal is observed in the accessible mass range
MeV, and upper limits are placed on the branching fraction product
as
a function of the mass and lifetime of the boson. These limits are of
the order of for lifetimes less than 100 ps over most of the
range, and place the most stringent constraints to date on many
theories that predict the existence of additional low-mass bosons.Comment: All figures and tables, along with supplementary material, are
available at
https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-036.htm
Measurement of the branching fraction ratio
Using collision data collected by LHCb at center-of-mass energies
= 7 TeV and 8 TeV, corresponding to an integrated luminosity of 3
fb, the ratio of the branching fraction of the decay relative to that of the
decay is measured to be 0.268 0.032 (stat) 0.007 (syst) 0.006
(BF). The first uncertainty is statistical, the second is systematic, and the
third is due to the uncertainties on the branching fractions of the and decays. This
measurement is consistent with the previous LHCb result, and the statistical
uncertainty is halved.Comment: 17 pages including author list, 2 figure
Study of and decays and determination of the CKM angle
We report a study of the suppressed and favored
decays, where the neutral meson is detected
through its decays to the and CP-even and
final states. The measurement is carried out using a proton-proton
collision data sample collected by the LHCb experiment, corresponding to an
integrated luminosity of 3.0~fb. We observe the first significant
signals in the CP-even final states of the meson for both the suppressed
and favored modes, as well as
in the doubly Cabibbo-suppressed final state of the decay. Evidence for the ADS suppressed decay , with , is also presented. From the observed
yields in the , and their
charge conjugate decay modes, we measure the value of the weak phase to be
. This is one of the most precise
single-measurement determinations of to date.Comment: 22 pages, 9 figures; All figures and tables, along with any
supplementary material and additional information, are available at
https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-020.htm
Study of boson production in association with beauty and charm
The associated production of a boson with a jet originating from either a
light parton or heavy-flavor quark is studied in the forward region using
proton-proton collisions. The analysis uses data corresponding to integrated
luminosities of 1.0 and collected with the LHCb detector
at center-of-mass energies of 7 and 8 TeV, respectively. The bosons are
reconstructed using the decay and muons with a transverse
momentum, , larger than 20 GeV in the pseudorapidity range
GeV
and . The sum of the muon and jet momenta must satisfy
GeV. The fraction of jet events that originate from beauty
and charm quarks is measured, along with the charge asymmetries of the
and production cross-sections. The ratio of the jet to
jet production cross-sections is also measured using the
decay. All results are in agreement with Standard Model predictions
Amplitude analysis of decays
The Dalitz plot distribution of decays
is studied using a data sample corresponding to of
collision data recorded by the LHCb experiment during 2011 and 2012. The data
are described by an amplitude model that contains contributions from
intermediate , , and
resonances. The model also contains components to describe broad structures,
including the and resonances, in the
S-wave and the S- and P-waves. The masses and widths of the
and resonances are measured, as are the complex
amplitudes and fit fractions for all components included in the amplitude
model. The model obtained will be an integral part of a future determination of
the angle of the CKM quark mixing matrix using decays.Comment: 33 pages, 12 figures; updated for publicatio
Measurement of the ratio of branching fractions
The branching fraction ratio is measured using a sample of proton-proton
collision data corresponding to 3.0\invfb of integrated luminosity recorded by
the LHCb experiment during 2011 and 2012. The tau lepton is identified in the
decay mode . The
semitauonic decay is sensitive to contributions from non-Standard-Model
particles that preferentially couple to the third generation of fermions, in
particular Higgs-like charged scalars. A multidimensional fit to kinematic
distributions of the candidate decays gives
. This result,
which is the first measurement of this quantity at a hadron collider, is
standard deviations larger than the value expected from lepton universality in
the Standard Model.Comment: 17 pages, 1 figure. v2 after referees' comment
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